逓減[teigen] gradual decrease
逓信[teishin] communications (e.g. post, tele.)
逓送[teisou] forwarding
逓増[teizou] gradual increase
逓伝[teiden] relay

駅逓[ekitei] delivery of packages
逓降変圧器[teikouhenatsuki] step-down transformer
逓次[teiji] successively
逓倍[teibai] multiplication (e.g. of frequencies)
逓倍器[teibaiki] multiplier (e.g. frequency)